Two of the top Republicans on the Senate Judiciary Committee are now questioning Susan Rice, the former national security adviser. They want to know about an “unusual” message she sent to herself on Jan 20, 2017 — President Trump’s Inauguration Day.

Chuck Grassley (R-Iowa), the Senate Judiciary Chairman, and Sen. Lindsey Graham (R-S.C.) questioned Rice on why she sent a note detailing a conversation she observed on Jan. 5 between then-FBI Director James Comey and then-President Barack Obama.

“It strikes us as odd that, among your activities in the final moments on the final day of the Obama administration, you would feel the need to send yourself such an unusual email purporting to document a conversation involving President Obama and his interactions with the FBI regarding the Trump/Russia investigation,” they wrote in a letter to Rice.

They also noted that in the message, Rice commented on how Obama repeatedly emphasized during the meeting on Russian election hacking with Comey that he wanted every aspect of the issue handled “by the book.”

“The President stressed that he is not asking about, initiating or instructing anything from a law enforcement perspective. He reiterated that our law enforcement team needs to proceed as it normally would by the book,” Rice wrote.

”From a national security perspective, however, President Obama said he wants to be sure that, as we engage with the incoming [Trump] team, we are mindful to ascertain if there is any reason that we cannot share information fully as it relates to Russia.”

The GOP senators indicated that despite Rice’s repeated mention of Obama emphasizing the need for proper investigation, “substantial questions have arisen about whether officials at the FBI, as well as at the Justice Department and the State Department, actually did proceed ‘by the book.’”

Grassley and Graham asked Rice to respond to about a dozen questions related to the message to herself, and they also wanted to know what she knew at the time about the Russia investigation. They asked whether she had “any reason to dispute the timestamp of the email” as well as other surrounding circumstances of her note.

The Senate Judiciary Committee is in the process of scrutinizing whether Obama-era officials sought to damage Trump’s presidential campaign during last year’s election.

Earlier this month, Republicans on the House Intelligence Committee released a classified memo with details that claimed the FBI and Justice Department gave misleading information to obtain a surveillance warrant application on Trump campaign aide Carter Page.

President Trump believes this memo vindicates him in the Russia probe, while other GOP lawmakers, including House Speaker Paul Ryan (R-Wis.), said it does not impact special counsel Robert Mueller’s investigation into Russian interference.